Electromagnetic coils are used in numerous applications to generate alternating or static magnetic fields. In most applications, it may be sufficient for the coils to be of a fixed diameter. Fixed diameter coils may therefore be used, e.g., in a variety of applications that require a magnetic field, such as solenoid actuators, conventional electrical motors, transformers, etc. One example of what is termed a collapsible coil for inspection of pipelines is described in U.S. Pat. No. 7,154,264. As discussed therein, a collapsible excitation coil includes a plurality of electrically interconnected collapsible excitation coil segments connected to a first end of what is described as an inspection pig structure along with inspection of pipelines that have obstructions which were said to prevent conventional inspection pigs from passing the obstructions.